has material basis in germline mutation in BCS1L autosomal recessive disease Bjornstad syndrome https://rarediseases.info.nih.gov/diseases/22/bjornstad-syndrome https://www.malacards.org/card/bjornstad_syndrome Bjrnstad syndrome is characterized by congenital sensorineural hearing loss and pili torti. Less than fifty cases have been reported so far. The hearing loss usually becomes evident very early in life, often in the first year. Pili torti, a condition in which the hair shaft is flattened and twisted, makes the hair very brittle and patients develop hair loss in the first two years of life. Bjrnstad syndrome is transmitted as an autosomal recessive condition. It is caused by mutations in the BCS1L gene. Mutations in this gene also cause GRACILE syndrome. MEDGEN:82728 deafness-pili torti-hypogonadism syndrome PTND PTD DOID:0050677 MESH:C537633 deafness and pili torti, Bjornstad type BJS UMLS:C0266006 OMIM:262000 Bjornstad syndrome MONDO:0009872 Orphanet:123 GARD:0000022 NORD:859 pili torti-sensorineural hearing loss Björnstad Syndrome mitochondrial disease